Enhanced Catalytic Performance of FeMnO x Catalysts Synthesized via Agar Method for Toluene Oxidation: Synergistic Effects and Degradation Mechanism

ABSTRACT Herein, FeMnO x composite catalysts were synthesized using the agar method, aiming to enhance the catalytic performance for toluene oxidation. Compared to traditional preparation methods, the agar‐gel technique leveraged the unique templating effect of biopolymer gels, which promoted the uniform dispersion and crystallization of the Fe‐O‐Mn structure, leading to the formation of abundant oxygen vacancies and surface defect sites. Results indicated that the catalytic performance of FeMnO x ( T 90  = 225°C) was significantly superior to that of single‐metal oxides, attributed to the enhanced Mn 3+ content, O ads , and oxygen mobility induced by the Fe‐Mn synergistic effect. Systematic characterization confirmed that the strong interaction between Fe and Mn in FeMnO x reduced the Mn‐O bond strength and optimized the adsorption and activation capabilities of oxygen species. In situ DRIFTS analysis further revealed the unique reaction pathway of FeMnO x : benzoic acid could be directly converted to maleic anhydride, circumventing the formation of phenol intermediates, thereby reducing the accumulation of by‐products and accelerating the deep oxidation of toluene to CO 2 and H 2 O. This research presented a novel strategy for the green synthesis of efficient Fe‐Mn catalysts and provided an innovative approach to the catalytic degradation of toluene.